America's number one. And for a local Australian landmark. This 65 stories smokestack in Sydney was toppled in a controlled explosion and thousands of people watched as 7000. Tons of concrete steel and bricks. To the ground.

This transcript has been automatically generated and may not be 100% accurate.

Demolition Leaves Spectators in Cloud of Dust

A wind change left a crowd watching the demolition of a building in Paris blown over by dust.

Demolition Spectators Injured by Flying Shrapnel

Implosion at a California power plant partially amputated one man's leg and injured several others.

Smokestack Explosion Backfires

A planned demolition of three smokestacks goes horribly wrong.

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